1. The Field of the Invention
The present invention relates to systems, methods, and apparatus for testing optical transmitter, receiver, and transceiver components. In particular, the present invention relates to testing printed circuit board assembly subcomponents.
2. Related Technology
Fiber optic technology is increasingly employed as a method by which information can be reliably transmitted via a communications network. Networks employing fiber optic technology are known as optical communications networks, and are marked by high bandwidth and reliable, high-speed data transmission.
Generally, multiple fiber optic components are designed to accomplish different aspects of these aims. For example, an optical transceiver has both optical sending and optical receiving capabilities, and can include one or more optical subassemblies (“OSA”) such as a transmitter optical subassembly (“TOSA”), and a receiver optical subassembly (“ROSA”). Typically, each OSA is created as a separate physical entity that includes electrical circuitry for handling and converting the appropriate electrical and optical signals. Within the optical transceiver, each OSA generally includes electrical connections to various additional components such as a transceiver substrate, sometimes embodied in the form of a printed circuit board (“PCB”).
The transceiver substrate can include multiple other active circuitry components particularly designed to drive or handle electrical signals sent to or returning from one or more of the electrically-attached OSAs. Accordingly, such a transceiver substrate will usually include a number of electrical transmission lines along with the one or more OSAs. These transmission lines are connected between the transceiver substrate and the OSA using different types of electrical connectors.
Assembling optical transceiver devices from optical components can include complicated and costly manufacturing processes. Due at least in part to the manufacturing complexity, assembled optical transceivers are often tested prior to use. For example, in order to ensure that an optical transceiver device is suited for an intended use, the manufacturer will often put the optical transceiver device through extensive testing procedures. The testing procedures are typically designed to ensure that optical transceiver devices are properly assembled, and to ensure that the optical transceiver device will perform properly within certain parameters. Optical transceiver tests often include a trained human tester using a testing apparatus, such as an “evaluator board”, that is designed to simulate an operating environment.
Typically, “evaluator boards” are printed circuit boards that include a number of components such as one or more active circuitry components, one or more mounting positions for an optical device and, in some cases, one or more computerized system connection ports (e.g., a serial or parallel port, etc.). Evaluator boards, however, can be complex and therefore difficult to configure, particularly for testing small form factor (“SFF”) printed circuit board assembly (“PCBA”) subcomponents, including small form factor pluggable (“SFP”), and 10 gigabit small form factor (“XFP”) PCBA subcomponents.
For example, general testing procedures and apparatus often require additional parts to fit on or around an assembled optical transceiver device, such as downward or sideward mounting clamps that would mount around an OSA. Testing apparatus may also require other circuitry (in additional to circuitry already present on an evaluator board) such as one or more electrical connection interfaces that are placed beside or mounted over the assembled optical transceiver device, in order to couple the evaluator board to connector pins extending from the optical transceiver device.
Due to the complexity associated with mechanically configuring these types of testing apparatus, trained personnel may be required to appropriately operate the testing apparatus. Thus, an entity that desires to use these types of testing apparatus must expend resources to hire skilled personnel or alternately train personnel in the appropriate skills.
Beside mechanical configuration complexities and difficulties, other disadvantages exist with present testing procedures and apparatus. One disadvantage is that an evaluator board may not diagnose the source of a test failure such as, for an assembled optical transceiver, with sufficient specificity. Thus, the specific components within, for example, the assembled optical transceiver, causing the test to fail may not be identified. Accordingly, the manufacturer may need to disassemble the device and further analyze each subcomponent in the failed device to identity the cause of the test failure.
However, the cost of disassembly and further analysis of components may be prohibitive as compared to assembling and testing a new PCBA subcomponent. Thus, the manufacturer may simply throw the failed device away. Non-specificity of test results can be further exacerbated when a manufacturer delegates the manufacturing of subcomponents, such as of the transceiver substrate, to a third party. For example, faulty testing information about the source of PCBA subcomponent failure may cause the manufacturer to easily waste time and money evaluating working subcomponents, and may create difficulties when trying to designate replacement costs to any third-party subcomponent manufacturers.
Accordingly, an advantage can be realized with systems and methods that allow a manufacturer to accurately diagnose errors in the components of small form factor PCBA subcomponent. In particular, an advantage can be realized with systems and methods that are easily implemented by a subcomponent manufacturer, and allow the subcomponent manufacturer to diagnose errors in subcomponents prior to assembly on the relevant PCBA.